The surprise retirement announcement by U.S. Rep. Ed Pastor on Thursday set off a political chain reaction, with Democratic players across the Valley sizing up the rare open congressional seat, as well as offices that will be abandoned by officials who must resign to run for Congress.

The safely Democratic district offers a once-in-a-generation opportunity that could draw a host of candidates who have waited for years for Pastor to retire. Minutes after Pastor announced he would not run for re-election this year, local figures began promising to launch campaigns.

The highest-profile official to announce her candidacy was Maricopa County Supervisor Mary Rose Wilcox, who said she will resign the seat she has held since 1992 to run.

Democratic state Sen. Steve Gallardo and state Rep. Ruben Gallego also confirmed they will enter the race. And other state lawmakers and Phoenix City Council members left the question open.

Even the congressman’s daughter, Laura Pastor, who just took office as a Phoenix councilwoman in January, said she will consider it.

“Safe seats such as the central Phoenix one don’t come around very often,” said political consultant Barrett Marson, an independent. “District 7 voters will have a plethora of options. It’ll be a free-for-all that could easily eclipse the (10 candidate) primary election that followed (then-Rep.) John Shadegg’s retirement” in 2010.

Pastor’s departure will set off a “domino effect, from federal (offices) all the way down to city (councils),” said Mario Diaz, a longtime Hispanic political consultant who was one of Pastor’s first staff hires in 1991. “This is a once- or twice-in-a-lifetime opportunity.”

Observers say the open seat makes way for another Latino to be elected in a district that has long trended heavily Hispanic and Democratic. Two-thirds of the district is Hispanic, recent U.S. census figures show. Last election, they cast nearly one in two votes, according to data from the Arizona Democratic Party. In 2012, Pastor faced no serious Democratic challenger in the primary and won the general election with 82 percent of the vote.

But analysts say a non- Latino could also win, especially if a candidate can turn out neighborhoods in the northern and eastern sections of the district, where the gay community is strong.

“This is going to be an opportunity for the Latino community to flex its political muscle in Arizona once again,” Diaz said. “There’s also an opportunity for a White liberal candidate, perhaps LGBT, to win the seat,” Diaz added, referring to the lesbian, gay, bisexual and transgender community.

Bob Grossfeld, a Democratic political strategist, said the LGBT community’s political might is greater than the numbers would indicate. He said LGBT voters have a well-connected fundraising network that rivals Emily’s List, the powerful advocacy group for female politicians who support abortion rights.

“Given the central-city portion of the district, I would assume that (the LGBT community’s influence is) not insignificant,” Grossfeld said. “But you know, there’s no census that takes sexuality into account, so it’s really hard to guess, other than how vocal people are from different communities. And the LGBT community there is very vocal.”

Pastor, 70, the son of a miner from a small community in east-central Arizona and the first in his family to graduate from college, has represented parts of Phoenix and the West Valley in Congress for more than two decades. He was the first Hispanic from Arizona to be elected to Congress.

The 7th Congressional District encompasses much of south and central Phoenix, including the Arizona Capitol, Phoenix Sky Harbor International Airport and Phoenix City Hall. It also stretches into the communities of Glendale, Guadalupe and Tolleson.

Speculation about when Pastor would retire has swirled for years. Besides Pastor’s daughter, Wilcox, 64, has long been viewed as a successor. Observers say state Rep. Catherine Miranda also could have a good shot. Miranda is part of a longtime Arizona Hispanic political family.

But in recent years, a new generation of rising stars with ambitions for the seat, many Latino, has emerged, including Gallego, whose wife recently won a seat on the Phoenix council. If he went to Congress, Gallego, 34, and his wife could cement a family political dynasty similar to the Pastors, observers noted.

“This is going to be a narrative of the old guard versus the new guard within the Latino community,” Diaz said. “Mary Rose has had her engine warmed up for this seat for the past 23 years, and Ruben Gallego has been slobbering for this seat for a couple of years.”

Other up-and-comers considering the seat are Daniel Valenzuela, who joined the Phoenix council in 2012 after employing an eager force of young immigrants as volunteers, state House Minority Leader Chad Campbell and state Sen. Gallardo.

Former Phoenix Mayor Phil Gordon, current Phoenix Councilman Michael Nowakowski and Avondale Mayor Marie Lopez Rogers said they will consider running. The Rev. Jarrett Maupin, a Phoenix Black activist, said he will pray about the opportunity.

Alfredo Gutierrez, a former state lawmaker who grew up with Pastor, predicted Wilcox will be “the favorite” to win the seat, noting that her county district overlaps with the congressional seat.

“She knows that district better than anyone,” Gutierrez said, adding that Wilcox is a proven fundraiser and a “tireless” campaigner.

“I’ve been preparing myself. I feel good about it. I feel it is time,” Wilcox told The Arizona Republic. “I know (the district) like the back of my hand. I know the needs of the people. ... I’m ready to go.”

Wilcox has been the lone Democrat on the Board of Supervisors since she was elected to replace Pastor, also a Democrat, on the board in 1992. She is the longest-serving supervisor in the board’s history and its only female member.

Wilcox does not have to resign until she files her petition and affidavit of nomination for Pastor’s seat with the secretary of state. The period to file for the seat is between April 28 and May 28. She said she has not yet decided the timing. Once Wilcox resigns, the Board of Supervisors must appoint her replacement. Rules require her successor to be a registered Democrat who lives and is registered to vote in her district.

Some of the politicians rumored for the congressional seat, as well as a number of municipal leaders, could pursue Wilcox’s supervisor seat. But many would have to resign, setting off a cascade of local and state elections.

“That (Maricopa County) seat’s going to be a fight within itself within the Black community and the Latino community,” Diaz predicted.

Names of anticipated candidates already were being floated Thursday, and board staffers were being contacted by candidates exploring the seat.

The Board of Supervisors also must appoint replacements to seats vacated by legislators who resign to run for Pastor’s seat. But it is unclear if the board would pick replacements before the end of the session because those legislators are in their final terms.

Anyone who is appointed to a county elected office must run for the seat in the following election to complete the full term. Wilcox’s resignation will shake up a board that just began to stabilize after turnover in three of its five seats. Three new board members took office in 2013 after more than a decade of consistent membership.

Wilcox, an immigration activist, has been an outspoken critic of Sheriff Joe Arpaio, a characteristic that constituents may be looking for in her replacement, said Grossfeld, the Democratic strategist.

“I think her willingness to take on Arpaio is the thing that stands out the most,” he said. “That’s not an easy thing to do ... and she did it at a time when it probably just wasn’t very popular to do.”

Pastor told The Republic that he likely won’t endorse a successor and that instead of doling out his more than $1 million campaign war chest to candidates, he would like to donate it, similar to U.S. Sen. John McCain, who founded an institute using money left over from his presidential campaign. Ronnie Lopez, a Pastor campaign adviser, said the two had not yet decided what to do with his trove of district voter information and data.

Lopez laughed when asked why the congressman announced his retirement after his daughter won a council seat, when he could have announced earlier and given her a straight shot to succeed him.

“To do what you’re talking about, we would have to go through the drama, the conspiracy, like the ‘House of Cards,’ ” Lopez said, referencing the popular political drama. “That takes way too much energy. ... We did not have a discussion of transferring the congressional seat from the daddy to the daughter.”

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